The NIDCR DIR Scientific Cores provided research support for intramural investigators performing studies on dental and craniofacial diseases. The Gene Targeting Facility (GTF) allows investigators to "add" or "subtract" genes in mice to develop animal models of relevant human diseases for research and to discover the affect of specific genes on host physiology. The GTF generated chimeric mice resulting in germline transmission of the genes of interest. In addition new gene knockout and transgenic mice were created and/or re-established. The murine embryonic stem cell service successfully completed gene targeting experiments. The GTF also provided an important scientific support service by cryopreserving embryos from murine animal models. These services contributed to over 200 research and review publications (reported in ZIA projects). Testing is underway for additional services, including sperm and ovary cryopreservation and IVF services for murine models and development of additional murine embryonic stem cell lines. The DNA Sequencing Facility provided over 15,000 reactions for NIDCR DIR investigator-led research.